Open the store, then add a profile in X<BC and look for "Applicationframehost.exe" with the window title "store"

But there appears to be a bug, because its not working/detecting it. So by the looks of it, its not currently possible. Universal Apps in Windows behave differently and have been a consistent pain because ever Windows 10 version seems to slightly change the behaviour!
Also if you have another applicationframehost.exe (for mail or something else for example) it wont let you add a new profile for store... I'll look into that